FBX Units & Scale

FBX files say what unit their numbers are in, and different programs read that differently. This page explains how Vertexix handles units when it reads and writes FBX, so a model comes back out at the same size it went in.

Vertexix works in metres

Inside Vertexix, one unit is one metre, and every model is brought to that scale when it is loaded. To check or change how big your model is, use Set Mesh Size.

Importing FBX

An FBX file records its unit as a scale factor relative to centimetres. When you load one, Vertexix reads that factor and converts the model to metres. A file saved in centimetres, metres or any other unit arrives at its real size. Collada (.dae) files declare their unit too, and are handled the same way.

OBJ, PLY and STL files have no unit at all, so their numbers are read as they are written: a value of 1 becomes one metre.

Exporting FBX

Every FBX file Vertexix writes is labelled as centimetres. To match that label, Vertexix multiplies all positions by 100 on the way out, so a 2.12 m model is written as 212 cm. Blender, Maya, Unity and Vertexix itself read the unit label and convert back, so the model arrives at the same size it left.

If you open an exported FBX in a text viewer or a tool that ignores the unit label, the numbers will look 100 times larger than they did in Vertexix. That is expected: they are centimetres.

Other formats

Format	Unit written
FBX	Centimetres, labelled as centimetres.
glTF	Metres — the glTF standard requires it.
Collada	Metres, labelled as metres.
OBJ, PLY, STL	Metres. These formats have no unit label, so the program you open them in decides what a unit means.

Which formats your edition can export is listed on Formats & Edition Availability.